Working with insecure people is really tough. In order to keep their appearance up, they have to act like they got all their stuff together, all the time. They have to prove themselves over and over. This can unleash anger from your end, especially when they keep praising themselves or putting themselves first.

A couple of tips that might make working with an insecure person a bit easier:

• Recognize insecurity. Often, you’re irritated way before you realize that it is actually insecurity that drives the behavior. It might make things a lot easier if you know it is not something you did that's causing things.
• Try praising unsolicited a bit more. It may reduce their need to constantly ask for attention and reinforcement.
• Don’t criticize in public. I think criticizing in general should be dealt with in private, but especially with insecure people. I sometimes thought “it might be good for them to learn how to deal with this, it’ll make them stronger”, but it is almost always a bad idea to do this.
• Try different ways of helping them along. If you notice that their insecurities rise when you’re working closely together, try if it helps to give them a little more freedom, or to “direct” a little more. Clearer expectations might mean that there is less insecurity about the outcome.
• Remind yourself that the problem is not yours. You might feel hurt because someone puts themselves on the first place and neglects to mention your work, but keep remembering that this is not your problem. Rise above it. Others will notice.